The field of the present invention is clamping fixtures and in particular, clamping fixtures useful in automotive assembly operations.
Clamping fixtures are often utilized to position workpieces in preselected positions during the fabrication and assembly operation. There are several factors to consider when designing a clamping fixture. One such factor is the shape and size of the workpiece to be held. A second is the desired angular orientation of the workpiece to be held. A third is the clamping force desired on the workpiece.
Typically when a clamping fixture may be utilized on different sized or shaped workpieces or on workpieces to be held at different positions, a custom clamping fixture must be designed. A change in clamping force desired can also mandate that a new clamping fixture be developed.
It is apparent to those skilled in the art that if the clamping fixture must be customized for each particular workpiece the expense associated with holding various workpieces is escalated. It is desirable to provide a clamping fixture that can hold various thickness workpieces at a range of angular positions while at the same time provide predictable clamping force regardless of workpiece thickness.
To make manifest the above delineated and other manifold desires a revelation of the present invention is brought forth. In preferred embodiment the present invention provides a clamping fixture which includes a parallel-spaced multiple member base. Pivotally connected to the base is a handle. The clamping fixture also has first and second jaw levers.
The jaw levers at one extreme end have a compliant gripping surface to engage the workpiece in a non-marring manner. Opposite from the jaw end, the jaw levers have pivot ends. Between the jaw ends and the pivot ends the jaw levers have spacers connected thereto which are pivotally connected to each other to allow the jaw levers to have pivotal movement with respect to one another. At their pivot ends, the jaw levers are each connected to pivot links. The pivot links are pivotally connected to one another. The jaw lever spacers are also pivotally and slidably connected to the base members via a slot in the base members.
The above-noted arrangement allows the clamping fixture to angularly position itself with respect to workpieces of different orientations. The handle is pivotally connected to the base at approximately its mid point and is pivotally and slidably connected to one of the pivot links connected with the jaw lever. One of the spacers is slidably connected to its respective jaw lever and is spring biased away from the other jaw lever by Belleville washers which are captured on the back side of the jaw lever.
After a workpiece has been presented between the jaw end of the jaw lever, the handle is pivoted upwards causing the pivot links to assume a generally straight position and thereby compress the workpiece. Further upward movement of the handle causes the handle to have an over-center toggle effect, retaining the workpiece within the fixture. To release the fixture, the movement of the handle is reversed.
It is a feature of the present invention to provide a fixture which can retain various workpieces of various thickness at various angles.